When constructing electrical or electronic systems, separate components or assemblies are often provided which in subsequent working steps have to be functionally connected to one another. For this purpose a plurality of differing electrical connecting devices are known. In this case, multi-core ribbon cables have proved their worth, in particular for a connection for signal transmission between communicating electrical or electronic components.
A miniaturisation of conventional ribbon cables, which finds application in particular in the field of printed circuit boards, is represented by so-called flexible printed circuits (FPCs). With these, instead of wire strands parallel conductor tracks are applied directly on a flexible tape-like insulator. By this means, particularly small conductor diameters and also a dense arrangement of conductor tracks within the lead are possible. For the purpose of connecting pcb components, for example, use is made, as a rule, of flexible printed circuits having a conductor density of one or two conductors per millimetre in the case of a width of the flexible printed circuit of up to several centimetres. For a connection of such flexible printed circuits, the sensitive ends of the conductor tracks are often clipped onto special plug-in connectors which require only a slight contact pressure, so-called zero-insertion-force connectors or ZIF connectors.
Above all in the field of the series production of consumer electronics or vehicle electronics an automated processing of flexible printed circuits is often desirable. In this case, however, besides the mechanical sensitivity of the thin ends of the conductors a particular difficulty consists in the fact that the quality of the connection between flexible printed circuit and plug-in connector depends sensitively on a correct geometrical orientation of the connecting parts. For example, just a slight offset or a tilting of the connecting parts relative to one another may result in an inadequate mechanical stability of the connection and also in a faulty contacting of one or more terminals.
At the same time, within the scope of an automated processing procedure the quality of the connection, or, to be more exact, the geometrical orientation of the connecting parts, can only be registered with difficulty and often not with sufficient precision. For instance, although it is known that differing types of wrong connections can be registered and displayed by video surveillance of the plug-in procedure, such a surveillance has proved to be relatively elaborate and, in addition, often not sufficiently reliable.